Texturing methods of abrasive grinding wheels: a systematic review

Creating textures on abrasive wheels is a strategy that allows a significant improvement in grinding operations. The reduction of the internal stresses in the workpiece and the temperature during the grinding operation generates an increase in the dimensional accuracy of the workpiece and a longer tool life. Textured abrasive wheels can be produced in many different ways. Depending on the processing method, the dimensional accuracy of the tool and its applicability is changed. Some methods can produce tools with three-dimensional grooves; there are also methods that are employed for the re-texturing of grooves after the grooved zone wears out. In the literature, the benefits of textured grinding wheels over traditional wheels have been extensively discussed. However, information on the particularities of texturing methods is still lacking. To clarify the advantages, limitations, and main advances regarding each of the groove production methods, the authors of this article carried out a systematic review. The objective of this work is to establish the factors that are affected by groove production methods and the technological advances in this area. The benefits and drawbacks of various grooving techniques are then reviewed, and potential study areas are indicated.This research was funded by FCT national funds, under the national support to R&D units grant, through the reference projects UIDB/04436/2020, UIDP/04436/2020, UIDB/00690/2020, UIDP/00690/2020, and SusTEC (LA/P/0007/2020). This work is within the scope of the Sharlane Costa Ph.D. degree in progress, financially supported by the Portuguese Foundation for Science and Technology (FCT) through the PhD grant reference 2021.07352.BD

Effects of Abrasive Grit Shape on Grinding Performance

The quality of grit in grinding wheel has predominate influence on the grinding wheel performance, such as wheel sharpness and wheel wear. This paper presents an investigation on the effect of difference grit shapes on grinding force and grit holding capacity. Some critical grinding behaviours are analysed in relation to grit shapes to establish a foundation for grit quality assessment. A desirable grit shape is identified for better cutting efficiency and grinding wheel life

Texturing methods of abrasive grinding wheels: a systematic review

Creating textures on abrasive wheels is a strategy that allows a significant improvement in grinding operations. The reduction of the internal stresses in the workpiece and the temperature during the grinding operation generates an increase in the dimensional accuracy of the workpiece and a longer tool life. Textured abrasive wheels can be produced in many different ways. Depending on the processing method, the dimensional accuracy of the tool and its applicability is changed. Some methods can produce tools with three-dimensional grooves; there are also methods that are employed for the re-texturing of grooves after the grooved zone wears out. In the literature, the benefits of textured grinding wheels over traditional wheels have been extensively discussed. However, information on the particularities of texturing methods is still lacking. To clarify the advantages, limitations, and main advances regarding each of the groove production methods, the authors of this article carried out a systematic review. The objective of this work is to establish the factors that are affected by groove production methods and the technological advances in this area. The benefits and drawbacks of various grooving techniques are then reviewed, and potential study areas are indicated.This research was funded by FCT national funds, under the national support to R&D units grant, through the reference projects UIDB/04436/2020, UIDP/04436/2020, UIDB/00690/2020, UIDP/00690/2020, and SusTEC (LA/P/0007/2020). This work is within the scope of the Sharlane Costa Ph.D. degree in progress, financially supported by the Portuguese Foundation for Science and Technology (FCT) through the PhD grant reference 2021.07352.BDinfo:eu-repo/semantics/publishedVersio

Analysis and Computer-Aided Simulation of Dressing of Grinding Wheel by Rotary Diamond Dresser

北見工業大学博士（工学）2013doctoral thesi

Development of Multi-grit cBN Grinding Wheel for Crankshaft Grinding

Crankshaft is a geometrically challenging component to grind. Over the years a number of grinding strategies have been developed to overcome thermal damage issues and excessive wheel wear. Radial and angular plunge processes have been adopted on some of the production machines. Recently a new, temperature-based strategy, has been proposed. A continuation project was launched, focusing on grinding wheel development and the initial work is presented in this thesis.A series of grinding trails have been used to correlate the grit properties with the grinding performance. The two evaluated grit characteristics are newly proposed aspect ratio (\u1d434\u1d445) and the concentration in the grinding wheel. The results show that blockier particles (lower\u1d434\u1d445) generate high forces and lower grinding wheel wear. On the other hand, the elongated particles require less power for grinding and act more free-cutting, improving the grindability. Further trials using higher concentration grinding wheels, exhibit similar behavior as grit(s) with lower \u1d434\u1d445. The two properties that are driving this performance are the contact area between the grinding wheel and the workpiece and the undeformed maximum chip thickness ℎ\u1d45a which changes with process and wheel design parameters

Laser Surface Structuring of Alumina

Alumina ceramic is an important abrasive material for grinding wheels used for rough grinding/machining of materials in manufacturing industry. Purpose of this work is to explore laser surface structuring of alumina grinding wheels for precision machining/grinding of materials by modifying surface microstructure of wheels. Major objective of this work is to study the evolution of surface microstructure and depth of modification such that microstructures/properties of modified wheels can be efficiently tailored based on fundamental understanding of physical processes taking place during laser surface structuring. Surface structuring of alumina using a continuous wave Nd:YAG laser resulted in significant surface melting and subsequent rapid solidification. The surface modified alumina consisted of microstructure characterized by regular polygonal and faceted surface grains with well defined edges and vertices. Such multifaceted grains act as micro-cutting tools on the surface of grinding wheels facilitating micro-scale material removal during precision machining. The formation of faceted morphology is explained on the basis of evolution of crystallographic texture in laser modified alumina. Furthermore, complete crystallographic description of multifaceted morphology of surface grains is provided based on detailed analysis of surface micro-texture. Due to complexity of microstructure formed during laser surface structuring, a fractal analysisbased approach is suggested to characterize surface microstructures. Detailed analysis of the effects of laser interaction with porous alumina ceramic indicated that melt surface undergoes rapid evaporation resulting in generation of high (\u3e105 Pa) evaporationinduced recoil pressures. These pressures drive the flow of melt through underlying porous alumina during modification extending the depth of modification. An integrative modeling approach combining thermal analysis and fluid flow analysis resulted in better agreements between predicted and experimental values of depths of melting. Finally, improvements in microindentation fracture toughness of alumina ceramic are reported with increasing laser fluence. Such improvements in the fracture toughness seem to be derived from better surface densification and coarsening of grain structure. The understanding of the evolution of faceted morphology, depth of surface modifications and improvements in fracture properties in laser surface microstructured alumina ceramic reached in this work provides the foundation for tailoring of surface microstructures/properties of alumina grinding wheels for precision machining applications

Material removal modeling and life expectancy of electroplated CBN grinding wheel and paired polishing

Paired polishing process (PPP) is a variant of the chemical mechanical polishing process which facilitates defect mitigation via minimization of maximum force as well as effective planarization via profile driven determination of force gradient. The present embodiment of PPP machine employs two polishing wheels, radially spanning the wafer surface on a counter-gimbaled base. The PPP machine is deployed to experimentally investigate the role of the process parameters on the surface roughness evolution, and the effective material removal rate. Two sets of copper and aluminum blanket layers were polished under a range of applied down force, polishing wheel speed and transverse feed rate to examine the scalability of the process parameters for different material constants. The experimental measurements along with the topological details of the polishing pad have been utilized to develop a mechanistic model of the process. The model employs the soft wheel-workpiece macroscopic contact, the polishing wheel roughness and its amplification to the local contact pressure, the kinematics of abrasive grits at the local scale, and the collective contribution of these individual micro-events to induce an effective material removal rate at the macroscale. The model shows the dependence of the material removal on the ratio of wheel rotational to feed speed for the PPP process, in a form of an asymptote that is scaled by the surface hardness of each material. The PPP machine exploits this insight and utilizes an oblique grinding technique that obviates the traditional trade-off between MRR and planarization efficiency. High speed grinding with cubic boron nitride (CBN) wheels are industrially attractive options for hard-to-machine metallic alloys, due to their low cost, reliability, reduced thermal damage and superior workpiece surface finish. However, thermal issues and transient behavior of the grinding wheel wear directly affect the workpiece surface integrity and tolerances. This thesis investigates the topological evolution of an electroplated CBN grinding wheel, characterization of its wear and life expectancy, when utilized in nickel-based alloy grinding. Depth profiling, digital microscopy and scanning electron microscopy are utilized to investigate topological evolution and mechanisms of grit failure. The results are used to elucidate the statistical evolution of the grinding wheel surface. It is found that when a grit is pulled out, load redistribution commences in its neighboring domain, with localized rapid grit wear. The unique experimental findings are used to develop a novel phenomenological model for the progressive wheel wear, including the combination of grit pullout (Stage I) and grit wear (Stage II). For Stage-I, the model employs the grinding kinematics, thermal shock to the grit-wheel interface, Paris law type fatigue approach. For Stage-II, Preston type wear approach is employed. The molding framework is utilized to infer electroplated CBN grinding wheels’ life expectancy for the high speed grinding and high efficiency deep grinding (HEDG) processes. The model provides the process design domain for different grinding process parameters, while maintaining a targeted wheel life, and averting potential damage of the workpiece

Wear evolution and stress distribution of single CBN superabrasive grain in high-speed grinding

In this study, both finite element analysis (FEA) and experimental observations were used to investigate the single CBN grain wear in high-speed grinding of Inconel 718 superalloy. The wear characteristics for each grinding pass were numerically assessed utilizing the tensile and compressive strength limits of the cutting grain. Additionally, stress distribution within the grain, chip formation and grinding force evolution during multiple passes were investigated. The combined experimental and numerical results show that the CBN grain wear has two major modes: the macro fracture on the grain top surface propagating from the rake surface, and the micro fracture near the cutting edges. The resultant tensile stress is the main factor inducing grain wear. The cutting edges will be under self-sharpening due to the grain wear. With multiple micro cutting edges engaged in grinding process, the limited material removal region was divided into different sliding, ploughing and cutting dominant regions. Overall, the ratio of material elements removed by a cutting process ranges from 80% to 20%, and continue to decrease during the grinding process. With a stronger effect of the cutting process, larger fluctuation of the grinding force will commence, however its average value remains below that with stronger sliding and ploughing process characteristics

Modelling the wear evolution of a single alumina abrasive grain: Analyzing the influence of crystalline structure

The grinding process is continuously adapting to industrial requirements. New advanced materials have been developed, which have been ground. In this regard, new abrasive grains have emerged to respond to the demands of industry to reach the optimum combination of abrasive-workpiece material, which allows for both the minimization of wheel wear and increased tool life. To this end — and following previous experimental works — the present study models in 3D the wear behavior of Sol-Gel alumina abrasive grain using Discrete Element Methods. It is established that the alumina behaves as a ductile material upon contact due to the effect of high temperature and pressure. This model reproduces the third body generation in the contact, taking into account the tribochemical nature of the wear flat, which is the most harmful type of wear in the grinding process. The evolution of the wear during a complete contact is analyzed, revealing similarities in the wear of white fused alumina (WFA) and Sol-Gel (SG) alumina. However, the SG abrasive grain suffers less wear than the WFA under the same contact conditions. The proposed wear model can be applied to any abrasive-workpiece combination

Tribology of Machine Elements

Tribology is a branch of science that deals with machine elements and their friction, wear, and lubrication. Tribology of Machine Elements - Fundamentals and Applications presents the fundamentals of tribology, with chapters on its applications in engines, metal forming, seals, blasting, sintering, laser texture, biomaterials, and grinding